diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 7cdd2d4e2..1f8e39903 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -158,6 +158,7 @@ jobs:
     - name: tests
       env:
         CTEST_OUTPUT_ON_FAILURE: ON
+        DNS_PUBLIC: tcp://9.9.9.9
       run: |
         ${{env.CCACHE_SETTINGS}}
         ${{env.BUILD_DEFAULT_LINUX}}